function used to parse the list of concepts of a SDMX-ML documents, to ensure backward compability with SDMX 1.0 that does not handle concepts in a concept scheme
Usage
concepts.SDMXConcepts(xmlObj)
Arguments
xmlObj
an object of class "XMLInternalDocument"
Warning
concepts.SDMXConcepts is a function used internally to parse the list of concepts during instantiation of "SDMXConcepts" objects